html,
body,
.box {
  height: 100%;
  margin: 0;
}
.box {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  min-width: 1000px;
  zoom: 1;
  background: url("../imgs/pc-bg.png");
  background-repeat: no-repeat;
  background-size: cover;
  -webkit-background-size: cover;
  -o-background-size: cover;
  background-position: center0;
}


